What's the power source? Load? Allowable peak current? Response time?
Example, a small SMPS source probably won't deliver enough fault current to clear a fuse. But it's current limited anyway, so it doesn't matter.
If you don't know the answers to these questions, then to what end are you looking? If it's protecting wiring, any fuse will do. if it's protecting transistors, an active current limiter (or voltage crowbar, as the case may be) is needed. There's an answer for everything, but finding the correct one requires more information.

Tim